The density of acetonitrile (CH3CN) is 0.786 g/mL, and the density of methanol (CH3OH) is 0.791 g/mL. A solution is made by dissolving 22.0 mL CH3OH in 98.4 mL CH3CN. Part A What is the mole fraction of methanol in the solution?

The answer to your question is  0.22

Explanation:

Data

Acetonitrile (CH₃CN) density = 0.786 g/ml

Methanol (CH₃OH) density = 0.791 g/ml

Volume of CH₃OH = 22 ml

Volume of CH₃CN = 98.4 ml

Process

1.- Calculate the mass of Acetonitrile and the mass of Methanol

density = mass/ volume

mass = density x volume

Acetonitrile

        mass = 0.786 x 98.4

                  = 77.34 g

Methanol

        mass = 0.791 x 22

                  = 17.40 g

2.- Calculate the moles of the reactants

Acetonitrile molar mass = (12 x 2) + (14 x 1) + (3 x 1)

                                        = 24 + 14 + 3

                                        = 41 g

Methanol molar mass = (12 x 1) + (4 x 1) + (16 x 1)

                                      = 12 + 4 + 16

                                      = 32 g

Moles of Acetonitrile

                     41 g 1 mol

                      77.34g  x

                      x = (77.34 x 1) / 41

                      x = 1.89 moles

Moles of Methanol

                      32 g 1 mol

                       17.40 g  x

                       x = (17.40 x 1)/32

                       x = 0.54 moles

3.- Calculate the mole fraction of Methanol

Total number of moles = 1.89 + 0.54

                                       = 2.43

Mole fraction = moles of Methanol / total number of moles

Mole fraction = 0.54/ 2.43

Mole fraction = 0.22  

iron and sleel

make siroeel

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6